Resistance training device and method

ABSTRACT

Devices, methods and systems for strength training directed at improving a bicyclist&#39;s performance. The training device includes a cycle frame, a seat and a set of handlebars and a crank arm assembly attached to the frame. The training device also includes a means for selecting an amount of resistance to rotational motion of the crank arm assembly. In use, a user advances the pedals and crank arms by pedaling against the selected resistance through a selected training arc, then returns the crank arms to the starting position, against negative resistance, and repeats the extension/retraction motion according to the strengthening protocol in use. The user then selects a second training arc and repeats the sequence of rotation against resistance and counter-rotation against negative resistance.

RELATED APPLICATIONS

This application claims the benefit of the filing date of a prior-filedProvisional Application Ser. No. 61/323,825 entitled Training Cycle andMethod, filed Apr. 13, 2010, which is incorporated by reference herein.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to athletic training devices andmore particularly to a weight training device that is adaptedspecifically for strengthening those muscles and muscle groups utilizedby the bicyclist.

2. Background

Exercise bicycles or cycling training devices in general are well known.To the extent that the prior art has addressed the training needs of thecyclist, however, those devices and methods are directed primarily tothe cardiovascular and endurance demands of the sport, while overlookingthe benefits that may be realized by the cyclist through strengthtraining directed specifically at strengthening those muscles and musclegroups utilized by the bicyclist.

The prior art teaches a variety of exercise devices including pedalconfigurations that offer resistance to rotation in either direction.See for example, U.S. Pat. No. 7,625,318 to Heyn, U.S. Pat. No.6,976,940 to Schneider, U.S. Pat. No. 5,368,535 to Twardokens and U.S.Pat. No. 5,354,249 to Raley. While resistance and weight trainingdevices have been designed for specific sports that involves a repeatedcomplex leg movement, (see for example, U.S. Pat. No. 5,284,460 toMiller, et al., and U.S. Pat. No. 4,781,372 to McCormack), to date therehave been none that have been directed specifically at strengtheningthose muscles and muscle groups utilized by the bicyclist.

FIG. 1 depicts a cycle training device according to the prior art thatfocuses solely on the cardiovascular aspects of training for acompetitive cyclist. Consistent with the teaching of the prior art, FIG.1 shows a training cycle wherein pedaling against a selected resistanceoccurs in a forward rotation FR and the resistance to rotation RTRresists said forward rotation of the pedals.

Therefore, advantage may be found in providing a weight training deviceand method that specifically addresses the strength training need of thebicyclist. Additional advantage may be found in providing a weighttraining device and method that allows the bicyclist to strength trainthose muscles and muscle groups in isolation, with the same patterns ofmuscle action and joint angles, and utilized by the bicyclist while thecyclist assumes a position on the training device that mimics theposition and muscular movements that the cyclist assumes relative to thebicycle during actual riding conditions.

Therefore one object of the present invention is to provide a weighttraining device and method that specifically addresses the strengthtraining need of the bicyclist according to well accepted principles ofexercise physiology, and particularly a device that enables isolatedstrength training for both the downstroke and upstroke muscle groupspertaining to both the left and right-side movements, and withresistance applied to both the concentric and eccentric muscle actionsof each exercise. Another object of the present invention is to providea weight training device and method that allows the bicyclist tostrength train those muscles and muscle groups utilized by the bicyclistwith the same muscle movement patterns, degrees of muscle contraction,and joint angles of coordinated multi-joint movements (termed“specificity” by exercise physiologists), and while the cyclist assumesa position on the training device that mimics the position and bodilygeometry that the cyclist assumes relative to the bicycle during actualriding conditions including both sitting and standing positions.

SUMMARY OF THE INVENTION

The present invention is directed to a device and method for resistanceand strength training that specifically addresses the strength trainingneed of the bicyclist. More specifically, the present invention isdirected to a device and method that allows the bicyclist to strengthtrain those muscles and muscle groups, in isolation, utilized by thebicyclist while the cyclist assumes a position on the training devicethat mimics the position and bodily geometry that the cyclist assumesrelative to the bicycle during actual riding conditions. Additionally,the present invention is directed to a device and method to performmovements in a semi-circular, forward and reverse motion, withuninterrupted positive and negative resistance present throughout themovement.

In one embodiment, a cycle frame assembly is mounted in a stationaryfixed position. Fixed to the frame are a seat and a set of handlebars,preferably having a configuration including dimensions, frame angles andseating position that is similar to those that the user employs on abicycle that the rider typically uses for actual riding, for instance aroad, track, cyclocross, time trial, or mountain bicycle. The objectiveis to provide a bicycle-like frame that supports the user in a cyclingposition for any of the known cycling disciplines, including thestandard road/track/cyclocross position, the time trial position, andthe mountain biking position. In a preferred embodiment, the frameoffers adjustability for seat height and forward-back positioning, andfor handlebar height and forward-back positioning to accommodate avariety of riders exhibiting a variety of physical statures and sizes.

The cycle frame of the present invention also includes a crank armassembly similar to that of the typical bicycle in that it includes apair of crank arms each offset from the other by one-hundred and eightydegrees of rotation, with each of the crank arms including an attachedpedal. The device is further adapted so that the user may alternatelyposition either crank arm at start of rotation point, thereby enablingisolated downstroke and upstroke strengthening exercises for both theleft and right legs of the user. In one embodiment the crank armincludes a chain ring similar to that of a bicycle. Alternately and inlieu of a chain ring, the crank arm assembly may include a pulley orwheel attached for rotation with the crank arms.

Strength training that is specific to various cycling sports may beaccomplished according to the method of the present invention in thefollowing manner. A user advances the pedals and crank arms by pedalingagainst the selected resistance until the crank arms reaches a desiredlimit of rotation, then returns the crank arm to the starting position,against negative resistance, and repeats the extension/retraction motionaccording to the strengthening protocol in use.

In alternate embodiments of the invention, resistance to rotation andcounter-rotation may be produced hydraulically, fluidly, by mechanicalfriction, electro-magnetically, electrically, pneumatically and othersuch means or devices.

In other alternate embodiments of the invention, the chain ring, wheelor pulley of the chain ring assembly may be configured as an ellipticalchain ring, wheel or pulley. Additionally, the position of the primaryaxis of the ellipses may be varied with respect to the crank armpositions. Similarly, the device may include a feature wherein the crankarms may be changed for longer or shorter crank arms depending on arider's preference.

Alternately the device may include a controller such that the device maybe programmable such that resistance levels throughout the semi-circularrotation and counter rotation may be varied to simulate the use ofelliptical chain rings, or other such means of enabling varyingresistance throughout the motion.

The apparatus can be configured to provide both positive resistance toforward rotation and negative resistance to counter rotation oralternately positive resistance only, for instance resistance to forwardrotation or in the alternative, just a negative resistance, orresistance to counter rotation.

In yet another embodiment of the invention, and to offer versatility ina single training device, the training cycle of the present inventionmay be adapted to be switchable between a strength training mode and anaerobic training mode.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of a cycle training device according to the priorart;

FIG. 2 is a representative side view of a cycle training deviceaccording to the present invention;

FIG. 3 is a representative side view of a cycle training deviceaccording to the present invention;

FIG. 4 is a representative top view of a cycle training device accordingto the present invention;

FIG. 5 is a representative side view of a drive assembly and a freewheelassembly for a cycle training device according to the present invention;

FIG. 6 is a representative cutaway view of a freewheel assembly for acycle training device according to the present invention;

FIG. 7 is a representative side view of a sprag clutch for a cycletraining device according to the present invention;

FIG. 8 is a representative side view of a drive assembly and a freewheelassembly for a cycle training device according to the present invention;

FIG. 9 is a representative cutaway view of a freewheel assembly for acycle training device according to the present invention;

FIG. 10 is a representative side view of a sprag clutch for a cycletraining device according to the present invention;

FIG. 11 is a representative flow diagram for a method of trainingaccording to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIG. 2, training device 110 includes cycle frame 111including handlebars 112 and saddle 114 attached to an adjustable seatpost 115. Training device 110 also includes power assembly 120 includinga pair of pedals 124 attached to a pair of crank arms 123 which in turnare connected to crank sprocket 121. Flexible continuous drive member125 operatively connects crank sprocket 121 to drive sprocket 126.Resistance system 140 is configured to provide resistance R to forwardrotation FR of crank arms 123 as well as negative resistance NR to thereverse rotation RR crank arms 123. Drive controls 145 provides controlrequires to permit training device 110 to operate as a strength trainingdevice according to the teachings of the present invention as well as anaerobic training device as is common in the prior art. According to thepresent invention, resistance R to forward rotation FR and negativeresistance NR to counter or reverse-rotation RR may be producedhydraulically, fluidly, by mechanical friction, or other mechanicalmeans, electro-magnetically, electrically, pneumatically and other suchmeans or devices. Drive controls 145 also provides the capability topermit operation of power assembly 120 in a freewheeling manner topermit re-positioning of the pair of crank arms 123 to a desired angularstarting position without resistance to such movement.

FIGS. 3 and 4 show training device 10 including cycle frame 11 andresistance system 40 both attached to training system frame 50. Cycleframe 11 is not unlike those employed commonly for aerobic training, tothe extent that it includes handlebars 12 that are adjustable up anddown and fixable in a selected position employing stem positioner 13.Seat post 15 slideably engages downtube 19 and a height of saddle 14 isvertically adjustable and fixable in a selected position employing seatpost adjuster 16. Saddle 14 is adjustable forward and backward andfixable in a selected position with horizontal saddle positioner 17.

Training device 10 also includes power assembly 20 including a pair ofcrank arms 23A and 23B attached to crank sprocket 21. Pedals 24A and 24Bare attached to the pair of crank arms 23A and 23B respectively. Chain25 operatively connects chain sprocket 21 to freewheel assembly 30.Freewheel assembly 30 includes pulley wheel 31.

Resistance system 40 includes weight frame 45 that provides thenecessary structural support for weight stack 42 that is connected toweight frame 45. Weight stack 42 is not unlike those seen commonlyemployed in weight training devices known to those skilled in the art.Weight stack 42 includes a plurality of individual weights stacked oneatop another, each slideably engaging a pair of guide rails 41. Lift bar43 is formed having one or more apertures formed through itscross-section perpendicular to its primary axis as is also well known tothose skilled in the art. Lift bar 43 inserts through an aperture formedon a vertical axis through a cross-section of each of the plurality ofindividual weights comprising weight stack 42 as is also well known tothose skilled in the art. Each of the plurality of individual weightscomprising weight stack 42 also include an aperture formed on asubstantially horizontal axis, again as is known in the art. Lift bar 43includes a plurality of apertures formed along its length such that eachaperture aligns with one of the apertures formed on the substantiallyhorizontal axis of each of the plurality of individual weightscomprising weight stack 42. An amount of weight that is to act as theforce resisting rotation and which is to provide negative resistance NRto counter or reverse rotation of crank arms 23A and 23B is selectableby inserting pin 47 through a particular weight and a correspondingaperture formed on the substantially horizontal axis of each of theplurality of individual weights comprising weight stack 42.

Cable 44 attaches at a first end to lift bar 43 and passes through aseries of pulleys 46A-46F before attaching at as second end to pulleywheel 31. The second end of cable 44 is fixed to pulley wheel 31 by endclamp 48 such that as pulley wheel 31 is rotated by movement of crankarms 23A and 23B and the attached crank sprocket 21 and chain 25, aforce equal to that portion of weight stack 42 that has been selectedresists angular movement of pulley wheel 31, the attached chain 25 andthereby crank sprocket 21 and the attached crank arms 23A and 23B.

FIGS. 5 and 8 show power assembly 20 including a pair of crank arms 23Aand 23B attached to crank sprocket 21. Pedals 24A and 24B are attachedto the pair of crank arms 23A and 23B respectively. Freewheel assemblyincludes sprocket 26 attached to pulley wheel 31. Chain 25 operativelyconnects chain sprocket 21 to sprocket 26 of freewheel assembly 30.Cable 44 is shown engaging pulley wheel 31 and is attached to pulleywheel 31 by end clamp 47. Due to the stresses encountered in the weighttraining routines that may be practiced with the present invention, thecomponents of power assembly, particularly crank arms 23A and 23B, cranksprocket 21 and chain 25 and sprocket 26 of the freewheel assembly 30are of substantially greater substance than typical bicycle components.

As shown in FIG. 5 upon forward rotation FR of pedals 24A and 24B andtheir respective attached crank arms 23A and 23B, depicted here in theclockwise direction designated as crank arm rotation CAR, causes aconsequential forward rotation FR of crank sprocket 21 and thereby chain25 and the operatively connected drive sprocket 26, designated assprocket rotation SR resulting in forward rotation of pulley wheel 31designated as pulley rotation PR. As pulley wheel 31 rotates, cable 44shown in FIGS. 3 and 4, is drawn about a circumference defined by pulleywheel 31, said pulley rotation PR being resisted by resistance R equalto a weight selected as described in reference to FIG. 3. Once pedals24A and 24B and their respective attached crank arms 23A and 23B havereached the bottom of training arc BTA, a controlled reverse rotation RRof crank arms 23A and 23B is initiated causing a consequential counterrotation of crank sprocket 21 and thereby chain 25 and the operativelyconnected drive sprocket 26, designated as sprocket counter rotation SCRresulting in counter rotation of pulley wheel 31 designated as pulleycounter rotation PCR.

FIGS. 6 and 9 show a cutaway view of freewheel assembly 30 includingdrive sprocket 26 attached to pulley wheel 31 by sprag clutch assembly35. Drive sprocket 26, pulley wheel 31 and sprag clutch assembly 35 areconnected to one another by bolt 34. As shown in FIGS. 6, 7, 9 and 10sprag clutch assembly 35 includes a plurality of sprags 38 disposedbetween inner race 36 and outer race 37. Sprag clutch assembly 35 servesas a freewheel device, and in this case inner race 36 operates as aninput member and outer race 37 serves as an output member. Sprag clutchassembly 35 is employed in the preferred embodiment as generallyspeaking a sprag clutch is capable to transmitting greater torque, for agiven overall dimension of the clutch than other types of freewheeldevices.

When sprocket rotation SR occurs at sprocket 26 as shown in FIG. 5,inner race 36 is rotated in the clockwise direction designated as innerrace rotation IRR as seen in FIG. 7. As shown in FIG. 7, a configurationof each of the sprags 38 is such that each of the sprags 38 wedgebetween inner race 36 and outer race 37 against a biasing force ofspring 39 transferring the torque of inner race rotation IRR to outerrace 37 providing outer race rotation ORR, which in turn provides pulleyrotation PR of the attached pulley wheel 31, (shown in FIG. 5). Oncesprags 38 engage both inner race 36 and outer race 37 and rotation ofpulley wheel 31 is initiated, the plurality of sprags remain wedgedbetween inner race 36 and outer race 37 due to the force of resistanceR, (shown in FIG. 5) against pulley wheel 31 and outer race 37. Thisfeature allows the user to sequentially rotate crank arms 23A and 23Bthrough training arc TA, shown in FIG. 5, against resistance R and thencounter or reverse rotate RR crank arms 23A and 23B through training arcTA in a controlled manner so as to not allow negative resistance NR toaccelerate the speed of crank arms 23A and 23B during reverse rotation.

Referring to FIG. 8, when a user desires to change an angularorientation of crank arms 23A and 23B so that alternate muscle groupsmay be isolated and subjected to resistance training, pedals 24A and 24Bwith their respective attached crank arms 23A and 23B arecounter-rotated, designated as crank arm counter-rotation CACR, to thedesired position. Counter-rotation of rank arms 23A and 23B causes aconsequential counter-clockwise rotation of crank sprocket 21 andthereby chain 25 and the operatively connected sprocket 26, designatedas sprocket counter-rotation SCR.

As seen in FIG. 10, as sprocket counter-rotation SCR occurs at sprocket26, inner race 36 is rotated in the counter-clockwise directiondesignated as inner race counter-rotation IRCR. As counter-rotation ofinner race 36 occurs a biasing force of spring 39 and a configuration ofeach of the sprags 38 is such that gap G is observed between each of theplurality of sprags 38 and outer race 37 such that sprocket 26 counterrotates in a “freewheeling” manner without engaging outer race 37 orpulley wheel 31, shown in FIG. 9.

In one study employing the device and methods of the present invention,performance of a group of female and male competitive cyclists andtri-athletes were tested. The subjects completed pre and post repeatedWingate anaerobic power tests with a two minute recovery between, alactate/ventilatory threshold test, initially one-hundred and fiftywatts at eighty revolutions per minute with the workload increasing bytwenty-five watts at two minute intervals until volitional fatigue, anda race simulation with repeated anaerobic sprints of thirty minutes atninety percent of ventilatory threshold. Subjects continued their usualaerobic training and used the strength training device twice a week forsix weeks.

Among other things, the results of testing demonstrated the following:

-   -   1. Peak power increased by approximately sixteen percent in the        training group, while the control group experienced a decrease        in this measure.    -   2. Anaerobic capacity improved by approximately fifteen percent        in the training group, while the control group experienced a        decrease.    -   3. Muscular endurance volume improved by approximately        forty-five percent in the downstroke and approximately        forty-eight percent in the upstroke in the training group, while        the control group experienced no change.    -   4. Muscular strength increased by approximately eleven percent        in the downstroke and approximately fifteen percent in the        upstroke in the training group, while the control group        experienced no change.    -   5. Total work in repeated sprints increased by approximately        twenty-one percent in the training group, while the control        group experienced no change.

FIG. 11 shows the steps of a METHOD FOR CYCLE STRENGTH TRAINING 200 thatincludes the steps of SELECTING A RESISTANCE FORCE TO A ROTATION OF THEOFFSET CRANK ARMS AND A NEGATIVE RESISTANCE FORCE TO A COUNTER-ROTATIONOF THE OFFSET CRANK ARMS 201, SELECTING A FIRST TRAINING ARC DEFINED BYA NUMBER OF DEGREES OF ROTATION THAT THE OFFSET CRANK ARMS WILL BEROTATED AGAINST THE RESISTANCE FORCE AND COUNTER-ROTATED AGAINST THENEGATIVE RESISTANCE FORCE 202, ROTATING THE OFFSET CRANK ARMS THROUGHTHE TRAINING ARC AGAINST THE RESISTANCE FORCE 203, COUNTER-ROTATING THEOFFSET CRANK ARMS THROUGH THE TRAINING ARC WHILE CONTROLLING THE OFFSETCRANK ARMS AGAINST ACCELERATION BY THE NEGATIVE RESISTANCE FORCE 204,and COUNTER-ROTATING THE OFFSET CRANK ARMS AGAINST A FREEWHEEL MECHANISMTO SELECT A SECOND TRAINING ARC 205.

While this invention has been described with reference to the describedembodiments, this is not meant to be construed in a limiting sense.Various modifications to the described embodiments, as well asadditional embodiments of the invention, will be apparent to personsskilled in the art upon reference to this description. It is thereforecontemplated that the appended claims will cover any such modificationsor embodiments as fall within the true scope of the invention.

1. A resistance training device comprising: a cycle frame including aframe, a seat connected to the frame and a set of handlebars connectedto the frame; a power system including a crank arm assembly attached tothe frame, the crank arm assembly including a pair of offset crank arms,the crank arm assembly adapted for rotation with respect to the frame;and a resistance system operatively connected to the to the powersystem, the resistance system including means for selecting a resistanceforce to a rotation of the crank arm assembly and a negative resistanceforce to a counter rotation of the crank arm assembly.
 2. The resistancetraining device of claim 1 further comprising a freewheel assemblyoperatively connected between the power system and the resistancesystem, the freewheel assembly configured to permit forward rotation ofthe crank arm assembly against the selected resistance force, thefreewheel assembly further configured to permit counter-rotation of thecrank arm assembly in a manner that controls acceleration of the crankarm assembly responsive to the selected negative resistance force, andthe freewheel assembly further configured to permit counter-rotation ofthe crank arm assembly in a freewheel mode when the resistance force andthe negative resistance force both equal substantially zero.
 3. Theresistance training device of claim 1 wherein the power system furthercomprises: a pair of pedals, each of the pair of pedals attached to oneof the pair of crank arms; a crank sprocket rotatably mounted to theframe, the crank sprocket rotatable by the pair of crank arms; asprocket rotatably mounted to freewheel assembly; and a flexiblecontinuous drive member connected between and rotatable with the cranksprocket and the sprocket.
 4. The resistance training device of claim 2wherein the freewheel assembly further comprises a sprag clutchconnected between the sprocket and the resistance system.
 5. Theresistance training device of claim 3 wherein the flexible continuousdrive member further comprises a chain.
 6. The resistance trainingdevice of claim 1 wherein the cycle frame further comprises a cycleframe selected from a group of cycle frames including cycle frameshaving the dimensions and frame angles of a road racing bicycle, a trackbicycle, a cyclocross bicycle, a time trial bicycle and a mountainbicycle.
 7. The resistance training device of claim 1 wherein theresistance system further comprises a weight stack operatively connectedto the to the power system, the weight stack including means forselecting a weight to resist the rotation of the crank arm assembly saidweight also providing the negative resistance to the counter-rotation ofthe crank arm assembly.
 8. The resistance training device of claim 1wherein the resistance system further comprises a resistance systemselected from a group of resistance systems including a mechanicalresistance system, an electrical resistance system, an electro-magneticresistance system, a hydraulic resistance system and a pneumaticresistance system.
 9. A resistance training device comprising: a cycleframe including a frame, a seat connected to the frame and a set ofhandlebars connected to the frame; a power system including a pair ofoffset crank arms rotatably mounted to the frame, a pair of pedals, eachof the pair of pedals attached to one of the pair of crank arms, a cranksprocket attached to and rotatable by the pair of crank arms, the powersystem further comprising a sprocket rotatably mounted to the frame, thepower system further comprising a flexible continuous drive memberconnected between and rotatable with the crank sprocket and thesprocket; a resistance system operatively connected to the to the powersystem, the resistance system including means for selecting a resistanceforce to a rotation of the crank arm assembly and a negative resistanceforce to a counter rotation of the crank arm assembly; and a freewheelassembly operatively connected between the power system and theresistance system, the freewheel assembly configured to permit forwardrotation of the crank arm assembly against the selected resistanceforce, the freewheel assembly further configured to permitcounter-rotation of the crank arm assembly in a manner that controlsacceleration of the crank arm assembly responsive to the selectednegative resistance force, and the freewheel assembly further configuredto permit counter-rotation of the crank arm assembly in a freewheel modewhen the selected resistance force and the selected negative resistanceforce equal substantially zero.
 10. The resistance training device ofclaim 9 wherein the freewheel assembly further comprises a sprag clutchconnected between the sprocket and the resistance system.
 11. Theresistance training device of claim 9 wherein the flexible continuousdrive member further comprises a chain.
 12. The resistance trainingdevice of claim 9 wherein the resistance system further comprises aweight stack operatively connected to the to the power system, theweight stack including means for selecting a desired weight to resistrotation of the crank arm assembly.
 13. The resistance training deviceof claim 9 wherein the cycle frame further comprises a cycle frameselected from a group of cycle frames including cycle frames having thedimensions and frame angles of a road racing bicycle, a track bicycle, acyclocross bicycle, a time trial bicycle and a mountain bicycle.
 14. Theresistance training device of claim 9 wherein the resistance systemfurther comprises a weight stack operatively connected to the to thepower system, the weight stack including means for selecting a weight toresist the rotation of the crank arm assembly said weight also providingthe negative resistance to the counter-rotation of the crank armassembly.
 15. The resistance training device of claim 9 wherein theresistance system further comprises a resistance system selected from agroup of resistance systems including a mechanical resistance system, anelectrical resistance system, an electro-magnetic resistance system, ahydraulic resistance system and a pneumatic resistance system.
 16. Amethod for cycle strength training that employs a strength trainingdevice including a cycle frame assembly having a frame, a seat and a setof handlebars and a crank arm assembly attached to the frame, the crankarm assembly including a pair of offset crank arms, the crank armassembly adapted for rotation with respect to the frame, means forselectively increasing or decreasing a force for resisting a rotationalmotion of the crank arm assembly, the strength training method includingthe steps of: selecting a resistance force to a rotation of the offsetcrank arms and a negative resistance force to a counter-rotation of theoffset crank arms; selecting a first training arc defined by a number ofdegrees of rotation that the offset crank arms will be rotated againstthe resistance force and counter-rotated against the negative resistanceforce; rotating the offset crank arms through the training arc againstthe resistance force; and counter-rotating the offset crank arms throughthe training arc while controlling the offset crank arms againstacceleration by the negative resistance force.
 17. The method for cyclestrength training of claim 16 further comprising counter-rotating theoffset crank arms to select a second training arc.
 18. The method forcycle strength training of claim 16 further comprising counter-rotatingthe offset crank arms against a freewheel mechanism to select a secondtraining arc.
 19. The method for cycle strength training of claim 16wherein the training arc is less than or equal to one-hundred and eightydegrees of rotation.